Convertible ladder



Dec. 22, 1931. H ALLEN 1,837,187

CONVERTIBLE LADDER Filed June 24, 1929 Z-Sheets-Sheet 1 /2 I /6 l 2a 4? 22 INVE OR Pe S ze/Z1102:

ATTORNE Dec. 22, 1931.- H LLEN 1,837,187

CONVERTIBLE LADDER Filed June 24, 1929 2 Sheets-Sheet 2 INVENTOR Percy H. JU/en ATTORN EY Patented Dec. 22, 1931 UNITED STATES PERCY H. ALLEN, OF SEATTLE, WASHINGTON CONVERTIBLE LADDER Application filed June 24, 1929. Serial no. 373,253.

This invention relates to ladders; and its object is to produce an improved ladder of inexpensive, strong and durable contruction which is adapted to be employed as a step ladder, or as a wall ladder.

A further object is to provide a construction which, as a step ladder, is adjustable to have the legs regulated to enable it to seat securely upon a bearing surface or surfaces disposed in different planes as upon a pair of steps of a staircase.

Another object is to provide a construction which, as a wall ladder is extensible to provide a rigid and strong ladder construction to various lengths.

Other objects and advantages of the. invention will appear in the following specification.

The invention consists in the novel construction, adaptation and combination of parts hereinafter described and claimed.

In the accompanying drawings,

Figure 1' is a perspective'view of an embodiment of my invention shown as arranged as a step-ladder for use upon a staircase; Fig. 2 is a fragmentary side elevation of the same with the members arranged as a stepladder for use upon a substantially horizontal support; Fig. 3 is a fragmentary longitudinal sectional View showing the ladder members arranged as an extensible straight or wall ladder; Fig. 4 is a view similar to Fig. 3 with the members arranged for use as a step-ladder as represented in Fig. 1; Fig. 5 is a front elevational View of the upper portion of Fig. 2; and Fig. 6 is a perspective view of one of the member-coupling devices illustrated in the preceding views.

According to the present invention I employ two straight ladder sections 10 and 11, hereinafter termed front and rear members, comprising side rails 12 and rungs 13 for the front member, and side rails 14 and rungs 15 for the rear member.

Said rear member is of greater width than the front member to accommodate the latter between the rails 12 of the rear section.

Rigidly secured as by means of bolts or rivets 16 to the upper ends of each ofthe side rails 14 of the rear member is a coupling 17 to furnish a seat for the rung 13 when the about its axis of oscillation to have the side (Fig. 6') of sheet metal, eachcoupling being formed to provide intermediate its width a web element 18 adapted to extend at right angles to the plane of the ladder members at 7 either side of the ladder and between the respective rails 12 and 14, the rear portion of each coupling extending, as a flange 19,

about the associated rail 14 to which the coupling is fixedly secured. a

The front portion of each coupling extends 00 as a stirrup 20 about the adjacent rail 12 to provide a slidable connection therewith for relative longitudinal movement and permitting a limited oscillatory movement to the front member 10. The axis of oscillation of the member 10 is located at approximately the mid-depth of couplings whereat the side web' 18 of each coupling is provided with a slot 21 of substantially the shape in which it is represented inFigs. 2 and 6 to receive ends 22 of the upper rung 13 which protrude laterally from the rails 12 of the front mem ber 10. As shown,each slot is provided with a downwardly directed inner end 21 "s ladder members are arranged as shown in Figs. 1 and 5 for use as a step-ladder upon a support which is level, or nearly so. For using the ladder as a step-ladder upon a base support which is inclined or in different planes, as upon steps-as A and B, Fig. 1, for instance, of a stairway-the couplings are disengaged from the rung 13 and the member 11 adjusted by moving the same downwardly upon the side rails 12 of the front member 10 into engaged relation with "any of the rungs 13, as may be required.- To furnish extended bearings for the rungs 13, Tprovide at the bottom of each coupling a side flange 24 with a rung receiving notch 24 in its underside.

For using the deviceas a straight or wall ladder, see Fig. 3, the two members 10 and 11 are regulated by swinging the member 10 rails 12 of such member bear against" the rungs 15 of the other member 11 and, after adjusting the ladder to a desired length, secure the two members together-"by means of bifurcated attachments 25straddling a rung of each member as shown with respect to rungs 13 and 15 of the ladder members. As shown, the attachments 25 are pivotally connected by means of bolts 26 to the rails of one of the ladder members.

It is to be noted that the ladder element 10 can be disengaged from element 11 by withdrawing the same, and as uncoupled, can be utilized as individual ladder units.

The invention and the manner of adjusting the same will, it is thought, be understood from the foregoing description.

What I claim, is,

1. In a convertible ladder, the combination of two ladder sections, coupling devices rigidly secured to the upper ends of the side rails of one section and havingslide connection with the side rails of the other section, said slidin section having a protruding upper rung, sai couplings being formed to present channels arranged to receive the side rails of said slidable section therein, the respective outer wings of said channels being notched in their upper edge for the detachable reception of said protruding upper rung of the slidable section, and the respective inner wings of said channels being notched in their lower edge for mounting the same over selective of the other rungs of said slidable section.

2. In a convertible ladder is defined in claim 1, wherein is provided means engageable with rungs of both sections and cooperating with the coupling devices for securing the two sections in aligned relations, one to the other.

3. In a convertible ladder having two ladder sections, and wherein one of said sections is arranged for sliding movement relative to the other, of means for securing said sections angularly with said ladder sections in selective dispositions of the slide movement of one to the other, said means comprising a plate rigid with one of said sections and conformed to present a notch in its underneath edge, said notch being adapted to straddle selective of the rungs of the other of said sections.

4. In an adjustable ladder having two ladder sections. and wherein one of said sections is arranged for sliding movement relative to a the other, of meansfor securing said sections in selective positions of their slide movement and angularly one to the other, said means comprising a plate carried bv one of said sections and conformedto straddle selective of the rungs of the other of said'sections.

In a convertible ladder, the combination with two ladder sections, one of which is slidable with respect to the other, said slidable section having an upper rung protruding laterally of the side rails thereof, of means cooperating with said protruding rung and the other rungs of the slidable section for securing said section in selective positions of its sliding movement, said means comprissubstantially vertically day of June, 1929.

PERCY H. ALLEN. 

